1. Field of Invention
The present invention relates to a driving circuit and, more particularly, to a driving circuit of a organic light emitting diode.
2. Description of Related Art
Display panels utilizing current coded mode comprise at least two driving periods. One is a data writing (current programming) period. In this period, a capacitor of a driving circuit is charged by a data current, that is to say, a data voltage is written into the capacitor. The other is a light emitting period. In this period, the display panel controls the displaying brightness thereof according to the data voltage written into the capacitor.
In the foregoing data writing period, the data current can be written into the capacitor in a short time when the data current is large. Consequently, conditions associated with the data writing period are not affected. However, the data current is relatively small when the display panel needs to display a low gray level such that the time in which the data current is written into the capacitor increases substantially. As a result, the duration of the data writing period is increased substantially, and furthermore, the operation of writing data may fail.